1 /* 2 * ACPI configfs support 3 * 4 * Copyright (c) 2016 Intel Corporation 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 */ 10 11 #define pr_fmt(fmt) "ACPI configfs: " fmt 12 13 #include <linux/init.h> 14 #include <linux/module.h> 15 #include <linux/configfs.h> 16 #include <linux/acpi.h> 17 18 #include "acpica/accommon.h" 19 #include "acpica/actables.h" 20 21 static struct config_group *acpi_table_group; 22 23 struct acpi_table { 24 struct config_item cfg; 25 struct acpi_table_header *header; 26 u32 index; 27 }; 28 29 static ssize_t acpi_table_aml_write(struct config_item *cfg, 30 const void *data, size_t size) 31 { 32 const struct acpi_table_header *header = data; 33 struct acpi_table *table; 34 int ret; 35 36 table = container_of(cfg, struct acpi_table, cfg); 37 38 if (table->header) { 39 pr_err("table already loaded\n"); 40 return -EBUSY; 41 } 42 43 if (header->length != size) { 44 pr_err("invalid table length\n"); 45 return -EINVAL; 46 } 47 48 if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) { 49 pr_err("invalid table signature\n"); 50 return -EINVAL; 51 } 52 53 table = container_of(cfg, struct acpi_table, cfg); 54 55 table->header = kmemdup(header, header->length, GFP_KERNEL); 56 if (!table->header) 57 return -ENOMEM; 58 59 ACPI_INFO(("Host-directed Dynamic ACPI Table Load:")); 60 ret = acpi_tb_install_and_load_table( 61 ACPI_PTR_TO_PHYSADDR(table->header), 62 ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL, FALSE, 63 &table->index); 64 if (ret) { 65 kfree(table->header); 66 table->header = NULL; 67 } 68 69 return ret; 70 } 71 72 static inline struct acpi_table_header *get_header(struct config_item *cfg) 73 { 74 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); 75 76 if (!table->header) 77 pr_err("table not loaded\n"); 78 79 return table->header; 80 } 81 82 static ssize_t acpi_table_aml_read(struct config_item *cfg, 83 void *data, size_t size) 84 { 85 struct acpi_table_header *h = get_header(cfg); 86 87 if (!h) 88 return -EINVAL; 89 90 if (data) 91 memcpy(data, h, h->length); 92 93 return h->length; 94 } 95 96 #define MAX_ACPI_TABLE_SIZE (128 * 1024) 97 98 CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE); 99 100 static struct configfs_bin_attribute *acpi_table_bin_attrs[] = { 101 &acpi_table_attr_aml, 102 NULL, 103 }; 104 105 static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str) 106 { 107 struct acpi_table_header *h = get_header(cfg); 108 109 if (!h) 110 return -EINVAL; 111 112 return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->signature); 113 } 114 115 static ssize_t acpi_table_length_show(struct config_item *cfg, char *str) 116 { 117 struct acpi_table_header *h = get_header(cfg); 118 119 if (!h) 120 return -EINVAL; 121 122 return sprintf(str, "%d\n", h->length); 123 } 124 125 static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str) 126 { 127 struct acpi_table_header *h = get_header(cfg); 128 129 if (!h) 130 return -EINVAL; 131 132 return sprintf(str, "%d\n", h->revision); 133 } 134 135 static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str) 136 { 137 struct acpi_table_header *h = get_header(cfg); 138 139 if (!h) 140 return -EINVAL; 141 142 return sprintf(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id); 143 } 144 145 static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str) 146 { 147 struct acpi_table_header *h = get_header(cfg); 148 149 if (!h) 150 return -EINVAL; 151 152 return sprintf(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id); 153 } 154 155 static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str) 156 { 157 struct acpi_table_header *h = get_header(cfg); 158 159 if (!h) 160 return -EINVAL; 161 162 return sprintf(str, "%d\n", h->oem_revision); 163 } 164 165 static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg, 166 char *str) 167 { 168 struct acpi_table_header *h = get_header(cfg); 169 170 if (!h) 171 return -EINVAL; 172 173 return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->asl_compiler_id); 174 } 175 176 static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg, 177 char *str) 178 { 179 struct acpi_table_header *h = get_header(cfg); 180 181 if (!h) 182 return -EINVAL; 183 184 return sprintf(str, "%d\n", h->asl_compiler_revision); 185 } 186 187 CONFIGFS_ATTR_RO(acpi_table_, signature); 188 CONFIGFS_ATTR_RO(acpi_table_, length); 189 CONFIGFS_ATTR_RO(acpi_table_, revision); 190 CONFIGFS_ATTR_RO(acpi_table_, oem_id); 191 CONFIGFS_ATTR_RO(acpi_table_, oem_table_id); 192 CONFIGFS_ATTR_RO(acpi_table_, oem_revision); 193 CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id); 194 CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision); 195 196 static struct configfs_attribute *acpi_table_attrs[] = { 197 &acpi_table_attr_signature, 198 &acpi_table_attr_length, 199 &acpi_table_attr_revision, 200 &acpi_table_attr_oem_id, 201 &acpi_table_attr_oem_table_id, 202 &acpi_table_attr_oem_revision, 203 &acpi_table_attr_asl_compiler_id, 204 &acpi_table_attr_asl_compiler_revision, 205 NULL, 206 }; 207 208 static const struct config_item_type acpi_table_type = { 209 .ct_owner = THIS_MODULE, 210 .ct_bin_attrs = acpi_table_bin_attrs, 211 .ct_attrs = acpi_table_attrs, 212 }; 213 214 static struct config_item *acpi_table_make_item(struct config_group *group, 215 const char *name) 216 { 217 struct acpi_table *table; 218 219 table = kzalloc(sizeof(*table), GFP_KERNEL); 220 if (!table) 221 return ERR_PTR(-ENOMEM); 222 223 config_item_init_type_name(&table->cfg, name, &acpi_table_type); 224 return &table->cfg; 225 } 226 227 static void acpi_table_drop_item(struct config_group *group, 228 struct config_item *cfg) 229 { 230 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg); 231 232 ACPI_INFO(("Host-directed Dynamic ACPI Table Unload")); 233 acpi_tb_unload_table(table->index); 234 } 235 236 static struct configfs_group_operations acpi_table_group_ops = { 237 .make_item = acpi_table_make_item, 238 .drop_item = acpi_table_drop_item, 239 }; 240 241 static const struct config_item_type acpi_tables_type = { 242 .ct_owner = THIS_MODULE, 243 .ct_group_ops = &acpi_table_group_ops, 244 }; 245 246 static const struct config_item_type acpi_root_group_type = { 247 .ct_owner = THIS_MODULE, 248 }; 249 250 static struct configfs_subsystem acpi_configfs = { 251 .su_group = { 252 .cg_item = { 253 .ci_namebuf = "acpi", 254 .ci_type = &acpi_root_group_type, 255 }, 256 }, 257 .su_mutex = __MUTEX_INITIALIZER(acpi_configfs.su_mutex), 258 }; 259 260 static int __init acpi_configfs_init(void) 261 { 262 int ret; 263 struct config_group *root = &acpi_configfs.su_group; 264 265 config_group_init(root); 266 267 ret = configfs_register_subsystem(&acpi_configfs); 268 if (ret) 269 return ret; 270 271 acpi_table_group = configfs_register_default_group(root, "table", 272 &acpi_tables_type); 273 return PTR_ERR_OR_ZERO(acpi_table_group); 274 } 275 module_init(acpi_configfs_init); 276 277 static void __exit acpi_configfs_exit(void) 278 { 279 configfs_unregister_default_group(acpi_table_group); 280 configfs_unregister_subsystem(&acpi_configfs); 281 } 282 module_exit(acpi_configfs_exit); 283 284 MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>"); 285 MODULE_DESCRIPTION("ACPI configfs support"); 286 MODULE_LICENSE("GPL v2"); 287